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71.
72.
矿物显微图像中网孔状及针板状成分识别方法研究 总被引:1,自引:0,他引:1
矿石的显微图像成分分析是一项具有挑战性的应用研究课题,针对所要求的对某种矿石进行自动识别的任务,提出了一种使用改进的统计假说方法对网孔状纹理成分进行识别的方法;并提出了一种采用Sobel变换、骨架提取以及Hough变换相结合的技术进行针板状纹理成分识别的方法,实验结果表明,该方法是有效的。 相似文献
73.
谢天泉 《冶金标准化与质量》2006,44(3):18-20
假设检验是统计技术较常用的一种分析测定结果进而推断化验室测定的方法、人员、实验室是否存在系统差异的技术。在质量管理中,假设检验具有以小概率事件来推断当工艺方法、原材料、过程参数改变时是否引起总体发生变化的常用方法。本文就某公司的子实验室与总部实验室每月的内外检结果(2004年1~2月)举例进行阐述。 相似文献
74.
Lau Anna S.; McCabe Kristen M.; Yeh May; Garland Ann F.; Wood Patricia A.; Hough Richard L. 《Canadian Metallurgical Quarterly》2005,19(3):367
The authors tested the acculturation gap-distress hypothesis by examining whether parent-adolescent acculturation gaps were associated with greater conflict and youth conduct problems among 260 high-risk Mexican American families. The authors operationalized acculturation gaps in 2 ways: parent-youth mismatches in acculturation style, and parent-youth discrepancies in acculturation toward both mainstream and heritage cultures. Acculturation gaps were common, but results of hierarchical regression analyses indicated that parent-youth discrepancies in acculturation toward mainstream and heritage cultures were not related to increased conflict or youth conduct problems. Conduct problems were no higher in families in which the adolescent was more aligned with mainstream culture than the parent. Unexpectedly, the authors found more youth conduct problems in families in which the youth was more aligned with traditional culture than the parent. The results call into question the assumption that the more rapid acculturation of adolescents to American culture inevitably leads to distress in minority families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
75.
Often quantitative data in the social sciences have only ordinal justification. Problems of interpretation can arise when least squares multiple regression (LSMR) is used with ordinal data. Two ordinal alternatives are discussed, dominance-based ordinal multiple regression (DOMR) and proportional odds multiple regression. The Q2 statistic is introduced for testing the omnibus null hypothesis in DOMR. A simulation study is discussed that examines the actual Type I error rate and power of Q2 in comparison to the LSMR omnibus F test under normality and non-normality. Results suggest that Q2 has favorable sampling properties as long as the sample size-to-predictors ratio is not too small, and Q2 can be a good alternative to the omnibus F test when the response variable is non-normal. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
This article presents strategies for treating child abuse survivors based on a theory of interpersonal protection that integrates research in attachment, developmental psychopathology, trauma, dissociation, and experiential psychotherapy. The theory proposes that abused children do not form internal working models of an effective protector, with the result that they have difficulty defending themselves against interpersonal aggression and internal self-criticism; thus, a core psychotherapy task is to help survivors develop adequate representations of protection. The article provides case examples and describes interventions targeting the client-therapist relationship, other client relationships, client self-criticism, and traumatic memories. The author discusses dissociation as an intervention marker; client verbal and nonverbal feedback to therapist interventions; subselves and internal roles; the "inner critic"; guided imagery, role-plays, and dramatic enactment methods; and directions for future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Urushihara Kouji; Wheeler Daniel S.; Pine?o Oskar; Miller Ralph R. 《Canadian Metallurgical Quarterly》2005,31(2):184
Three conditioned taste aversion experiments with rats investigated superconditioning. In each experiment, alternate exposures of 2 flavor compounds with a common element (i.e., AB/AS) were administered to establish an inhibitory relationship between the 2 unique elements, B and S, and prior to testing, S was paired with lithium chloride (LiCl). In Experiment 1, pairings of a neutral cue (X) with S in compound with B after the AB/AS exposures resulted in superconditioning between X and S. Extinction of the common element (A) just before the S-LiCl pairing attenuated both the inhibitory relationship between B and S (Experiment 2) and superconditioning between X and S (Experiment 3). These observations suggest that superconditioning consists of enhanced performance rather than enhanced associative acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
In 5 experiments, the authors tested whether the processing of nonconscious spatial stimulus information depends on a prior intention. This test was conducted with the metacontrast dissociation paradigm. Experiment 1 demonstrated that masked primes that could not be discriminated above chance level affected responses to the visible stimuli that masked them. Experiments 2 and 3 showed that this effect was abolished when the task instruction was changed in such a way that the primes ceased to be task relevant. Experiments 4 and 5 demonstrated that a prime's effect depended on whether it was associated with the same response as the target or with an opposite response. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
Estimation and hypothesis testing based on normal samples censored in the middle are developed and shown to be remarkably
efficient and robust to symmetric shorttailed distributions and to inliers in a sample. This negates the perception that sample
mean and variance are the best robust estimators in such situations (Tiku, 1980; Dunnett, 1982).
Professor Emeritus, Department of Mathematics and Statistics, McMaster University,
Professor Emeritus, Department of Mathematics and Statistics, McMaster University, 相似文献
80.
实时分布式系统中,如果结点n自从上一次收到结点i的广播信息后经过超时值时没有再收到结点i的广播信息,就认为结点i失败。这时需要调整各正常结点的优先列表,以保证每个结点被一个也只能是一个结点选择为自己的第后个优先结点,以减少任务的失败率。本文提出了一种确定最佳超时值以及检测结点失败并且调整结点的优先列表以处理结点失败的新方法。 相似文献